Why would smart people care about denim vs. trousers?
Let competitors wear pajamas- it makes no difference.
Mostly it's about the sponsors. It's much more difficult to get sponsors for an event if the participants are dressed like they slept in their clothes. That's why organizers try to impose minimal standards on dresscodes.
Jeans and sneakers are maybe debatable, but players showed up with cargo pants, shorts or tank tops on other events.
In the FIDE regulation for that event jeans were explicitly mentioned as not allowed. FIDE would have made a fool out of themselves when allowing Magnus to wear the jeans.
The best experience I have ever seen: Have the internal customer team hire a semi-technical fresh grad. They are the primary dog-fooder of the new app. Force them to do their job only using the new app (as much as possible). They give lots and lots and lots of immediate, direct feedback to the devs. You can slowly iterate to something reasonable. The secret that makes mid-level managers upset: Don't plan; allow it be built organically, especially if your audience is internal.
Another thing that I have noticed: Some people are just way, way, way better at designing and implementing GUIs. I have no idea how to filter for these people, but "you know it when you see it".
- Windows GUI went downhill from Windows 7 (or even XP) with every release.
- Outlook went from good over fair to annoying so that I finally replaced it as my personal client.
These are not the only examples I could name but they are the most prominent. I think the main problem is that both technical staff and UX designers both trying to make something "new" or "fancy" which is in most cases the opposite of something usable. E.g. Aero was fancy but it took away that my active window had one signal color header bar and all others were tamed. Now all windows are colorful and yelling at me at the same time. Orientation is gone.
And after that UIs got even more "fancy".
Step 13 ("Nobody's happy but nobody hates it") is the plateau when everybody is to tired to keep on fighting - a compromise, not the state of the GUI reached anything acceptable. It is not fancy enough anymore for developers and UX designers to be proud of but at the same time and is still annoyingly bad for the users.